ABS problems

[Allan Vincent]

Sorry guys, just been corrected by a member, my car is a diesel 2 litre (1950 cc)

[Arctic]

I had no doubt you had a diesel i was just trying to make sure you knew that it was 2.0 and not a 1.8 engine.

Personally i would not mess with the ABS modulator, it is not easy to get access to and needs to be opened with care as to not bend any pins etc.

After you have removed the battery the tray as to come out to.
1

The bracket as to be moved out of the way.
2

You will then have access to the modulator.
3

An wiring conduit will need to be removed to get access to the locking clip.
4

5

This clip then needs to be prised outwards, you can use a flat blade screw driver
6

It needs to be fully extended outwards, other wise it will not come apart.
7

Once fully out the wiring loom will lift off and expose the pins, these need to be checked for corrosion or damaged pins.
8

9

Fitting is the reverse, but as i say modulator is your last resort, get a T4 check and go from there.

[Allan Vincent]

OK guys, i got the message now, i'll book a T4 session with the garage in Newton Abbot. Thanks for the all the help. Cheers, Allan

[Mike Noc]

If you want to have a go yourself, courtesy of French Mike, you can check all the ABS sensors and magnetic reluctors in the wheel bearings using a voltmeter.

The signal voltage changes from 1.7V to 0.7V as each magnetic segment passes the sensor, so jack each wheel in turn and slowly rotate it marking the switch points on the tyre wall with chalk. You should end up with 48 chalk marks looking something like this:



If any gaps are in the same place each revolution then likely a damaged reluctor, and if in random places suspect the sensor.
Other common failure causes are cable damage to the sensors, flakes of corrosion interferring with the sensing, or corroded plug pins at the ABS modulator.

You connect the positive probe of the multimeter to the signal wire, and the negative to chassis earth:

I made up a cable from some old bell wire and a scrap ABS plug and socket to save pinning through the cable insulation. Here it is testing a hub prior to fitting:



Start with the OSR wheel as it often turns out to be the source of the fault. The OSR wheel on my car was missing quite a few segments, and needed a new bearing fitted:

[Allan Vincent]

Thanks for that I'll look into this. Amazing the help the club offers. Cheers Allan

Sent from my SM-T580 using Tapatalk

[stevehotshot]

That was an amazing post, full of lovely information for us geeks...love it...also it helped me to fix my ABS problem...Thanks